Calculate string

[Xa0z]

Does anyone now a function that can calculate a string like this

Ans = Calc("3*2+6^1-6/69.2*(6+4^(-1))")

I can write it myself I think, but It'll be a whole lot of work so if anyone nows of such a function, has it or even wrote it hisself, can you please give it to me.

[mlewis]

This code uses reverse polish notation (ie 2 2 + instead of 2 + 2) but you can write a converter that converts 2+2 to 2 2 + pretty easy.

[Serge]

Add a reference to Microsoft Script Control object library and do something like this:

Private Sub Command1_Click()
    Dim objSC As New MSScriptControl.ScriptControl
    
    objSC.Language = "javascript"
    
    MsgBox objSC.Eval("3*2+6^1-6/69.2*(6+4^(-1))")
End Sub

[Static]

Do a search on this.

I believe you can use the MS Scripting control and proccess it properly as a string.

[Mc Brain]

Originally posted by Serge
Add a reference to Microsoft Script Control object library and do something like this:

Private Sub Command1_Click()
    Dim objSC As New MSScriptControl.ScriptControl
    
    objSC.Language = "javascript"
    
    MsgBox objSC.Eval("3*2+6^1-6/69.2*(6+4^(-1))")
End Sub

Wow!! That's why I call a solution. Thanks for that tip!

[Xa0z]

Yes guys, thanks

[Tec-Nico]

Indeed it is a great solution... But why does it tell me the User Type is not defined?

What am I doing wrong?
If it works, will it be able to calcullate Logarithm, Sine, Cosine, etc.?

Please help me!

[Mc Brain]

Originally posted by Tec-Nico
Indeed it is a great solution... But why does it tell me the User Type is not defined?

What am I doing wrong?
If it works, will it be able to calcullate Logarithm, Sine, Cosine, etc.?

Please help me!

What's the code you're using?

[Tec-Nico]

I am using the same code Serge posted... Do I need something else?

[Mc Brain]

Add a reference to Microsoft Script Control object library and do something like this

[Tec-Nico]

I supposed that was the problem... But how can I add that reference?
Which is the code to do it?

Please help me, my brain is just not working in this moment...

[andreys]

Originally posted by Tec-Nico
Indeed it is a great solution... But why does it tell me the User Type is not defined?

What am I doing wrong?
If it works, will it be able to calcullate Logarithm, Sine, Cosine, etc.?

Please help me!

Add a reference to Microsoft Script Control 1.0 object library

[Mc Brain]

Click on Project -> References.... look for the one that was said and select it. Click on Ok to finish.

[Tec-Nico]

Guys... Are you meaning I have to go to "References" in the proyect of VB and add it as if it was just like a control?

Please be patient with me since my computer has not installed VB now due to a problem, so I am going back and forth from my computer to one that has VB in the computer center.

[Mc Brain]

Exactly... the difference is that you're not adding a control but a "reference" to the library. You're telling VB: "Hey, use this function as well!".

[Tec-Nico]

Oops.. Thank you guys, now it is working...

[Mc Brain]

You're welcome.

[Tec-Nico]

Just another doubt... Does it support sine, cosine, tangent and all that kind of mathematical functions?

[Mc Brain]

I don't know.... if you read the code you can realize that it's Java. If those functions are available in this language, you should write it that way.

[Tec-Nico]

Thank you again... I am going to check it when I get home.

I will install VB and check using the java format for these functions... If I get struck I will be back here...

Heh, heh, heh... Thanks once again and see you later!

[Mc Brain]

Ok... but I don't know "much" Java.

[techgnome]

The script control also supports VBScript.....
might be easier to work with.....

[Mc Brain]

I thought so... but never tried it, though.

[pnish]

I just tried the code using objSC.Language = "vbscript" and for the example equation:
"3*2+6^1-6/69.2*(6+4^(-1))"
I get the answer as 11.4580924855491

However if I use objSC.Language = "javascript" I get 13 as the answer.

Also if I type the equation into VB's immediate window I get 11.4580924855491

I'm too lazy (and brain dead at the moment) to try and figure it out on the old calculator. Which one's correct?

[Mc Brain]

11.4580924855491

[Tec-Nico]

Thanks for the tip, techgnome... Now it is working perfectly.

Look guys, I am programming a Numeric Method evaluator. This means the user can write down a complex mathematical function and then let the program get the results by using methods as Newton Rapshon. Now I can evaluate the function, but I need help to know when the user has typed a function that cannot be evaluated by the MSScript....

How can I tell if the string given can be evaluated or not?
Anysuggestions?


P.S. Use VBScript and not JavaScript, it is more effective and has less margin of error. Yet if you need Pi you must declare it in a constant in VBScript while JavaScript can automatically give it to you.